Carton unloader for containers



June 15, 1954 E. H. LORENZ Erm. 2,681,161`

CARTON UNLOADER FOR CONTAINERS Filed July e, 1951 5 shams-sheet 1 O O D O O O O O O O O 0 O O O O O 0.0 0. 0 0 0 O O O O 0 0 0 0 O .n0 N m K NNI.. MM. ..\\w.

R QQ June 15, 1954 E. H. LORENZ rs1-Ax.

CARTON UNLOADER FOR CONTAINERS 5 Sheetsf-Sheet 2 Filed July 6, 1951 `s Wm TRA Now EL VMS m w D RO www Y 8 A T TORNE YS June l5, 1954 E. H. LORENZ ETAL 2,681,161

CARTON UNLOADER FOR CONTAINERS Filed July 6, 1951 5 Sheets-Sheet 3 /NVENTORS EDWARD H. LORENZ THUMAS WUGH ATTORNEY;

June l5, 1954 E. H. LORENZ ETAL l 2,681,161

CARTON UNLOADER FOR CONTAINERS Filed July 6, 1951 5 Sheets-Sheet 4 l i i. n y hlzmi-.lz f

/NVENTORS EDWARD H. L OPENZ THUMAS WAUGH A T TORNEVS June 15, 1954 E. H. LORENZ ETAL 2,681,161

CARTON uNLoADER FoR CONTAINERS Filed July e, 1951 5 sheets-sheet '5 /NVENTORS EDWARD H. LORENZ THOMAS WA UGH ,wmf-JM A7' TORNEYS Patented June 1'5, 1954 UNITED STATES ATENT OFFICE CARTON UNLOADER FOR CONTAINERS ration of Delaware Application July 6, 1951, Serial No. 235,442

Claims.

This invention relates to improvements in apparatuses for removing articles, e. gv., containers, from their cartons or cases and more particularly to a carton unloader which is particularly designed and adapted to extract a plurality of rows of empty cans or the like from their case or carton as a group and to transfer them to a spaced suitable conveyor or other supporting surface.

Articles such as empty cans may-be packed in a carton so tightly that considerable force must be exerted in the direction of their axes to eX- tract them and there is very little space around the individual cans for entry of tongs or the like for gripping them. When this condition exists, prior devices which are designed to operate by stripping the cartons from the articles, either up-V wardly in the case of inverted cartons or downwardly when the cartons are upright, while the articles are constrained to follow a horizontal path of movement are not satisfactory.

' Other prior devices are designed to operate by moving grippers vertically downward into gripping engagement with the upper ends of the articles in an upright case or carton at anl unloading station and then lifting the engaged articles vertically upward from the case or carto-n along the path of descent ofthe grippers. These necessarily require intermittency of operation so-as to be undesirably slow.

vAn object of the invention is to provide operable pendant grippers on a continuously moving conveyor mounted-and operated firmly to engage and to remove as a group all the articles, such as cans, which lill an open-top carton at an unloading station and are packed therein in a plurality of parallel rows, each containing a plurality of the articles.

Another object of the present invention is to provide a carton unloading apparatus which will remove tightly, as well as more loosely, packed upright opens cans or similar articles from their carton positively and quickly.

A further object of the invention is to provide a carton unloading apparatus of the character described having means carried by a continuously moving conveyor for engaging the upper ends of the individual articles, such as empty cans, disposed in a plurality or" rows and fitting tightly in a carton, and for positively extracting these articles from'their carton without harmn ful pressure on or marring of the internal surfaces of the articles.

A still further object of the invention is to provide a carton unloading apparatushaving a continuously moving conveyor carrying one ormore spaced multiple article removing units,- each comprisingl article upper end-engaging devices correspondingin numbery and relative arrangementwith the articles in a cartonto-be unloaded and constructed and arranged to engage the upper ends of such articles without interference with one another, despite tight association of the articles in the carton and necessary restriction of relative lateral movements between movable .parts of adjacent article engaging devices- Other objects and advantages of the invention hereinafter will be pointed out or will become obvious from the following description of a practical embodiment of the invention, as shown inthe accompanying drawings, in which:

Fig. 1 is a longitudinal vertical section of the novel carton unloader approximately along the line l-I of Fig. 2, some elements of the supporting structure being partially broken away;4

Fig. 2 is a plan View of the carton unloader;

Fig. 3 is a relatively enlarged side elevation of one of the multiple article removing units of the apparatus;

Fig. 4 is a plan section along thevline li-Al of Fig. 3 of the article engaging devices of said unit, positioned above a carton which is shown in dot-and-dash lines;

Figs. 5 and 6 are fragmentary detail side elevations, each at a right angle with the other, of one of the article engaging devices;

Fig. 7 is a partial' plan view of the means for positioning and movably supporting a lledcarton at an unloading station with the carton at its initial or spotted position, the View also showing hold down means for certain of the flapsof the carton;

Fig. 8 is a partial View. like a right-hand portion ofV Fig. 7, showing the carton at a more ad.- vanced position along. its supporting means and the right hand nap hold down means at the position then occupied;

Fig. 9l is a View like Fig. 8 showing` the carton of the preceding-view ata further advancedposi.- tion and asecond'carton approaching theinitial or spottedposition of Fig. 7;

Fig. 10 is an, elevation of the carton withy a portion of its side wallbroken away and one of the cans therein shownin section, the viewaillusf` trating the eng-agement.. ofv the article engaging devices with individual cans in theY carton; and

Fig. 11 isa schematicperspective View showing the two transversely spacedparalleled cha-ins.VV of the unloader conveyortogether with a transverse carrier plate interposed between,` and attached to these chains so asf` always to be maintained horizontal duringmovement by the chains, and showing stationary guides for the chains andthe plate, additional positionsnf the plate during,- a cycle of the unloader; conveyor being indicated by dot-and-dash line.. showings of the projecting elements at the ends of the plate.

Generally and brieiiy described, the carton unloader of the invention comprises a rectangular frame structure I; Figs, 1, 2- and 11, sup* ported at a predetermined desirable height above a factory door or the like (not shown) by four uprights 2. Mounted within frame structure I is an unloader conv-eyor, generally designated 3, comprising a pair of transversely spaced staggered endless chains 4 and 5, respectively, lying in parallel vertical planes and carrying a plurality of spaced multiple article removal units 6, Figs. 1 and 2. Each unit 6 comprises `a. horizontally disposed carrier plate I having xed rigid laterally projecting lattaching strips 8 and 9, respectively, at two diagonally opposite corners thereof. See Figs. 2 and 11. Strip 8 is pivotally connected at its terminal end at 8a to a reinforced portion Fa of the chain 5 while the attaching strip V9 is similarly fastened at 9a to a similarly reinforced corresponding portion da of the chain 4. The other two diagonally opposite corners of each plate 'I are provided with projecting rigid strips I and II, respectively, carrying projecting rollers I2 and I3, respectively, at their extremities which are free from the conveyor chains. The chains are mounted and operated to move in unison along paths lying in parallel vertical planes so that the portions of the two chains to which two diagonally opposite corner portions of each plate 'I respectively are pivotally attached will always be at the same level, each with the other, and the plate thus will be carried in a constantly horizontal position by the chains throughout a complete cycle of movements of the conveyor. Suitable stationary guides for stretches of the chains and for co-action with the plate-carried rollers i2 and I3, respectively, may be provided, as later explained, to aid in keeping each plate horizontal and in stabilizing its movements by the conveyor chains.

Depending from the plate I of each unit 6 are article-engaging devices I4, Illa corresponding in number and relative arrangement with the articles in a carton to be unloaded, e. g., the cans I in a carton I6, Fig. 9, when that carton is disposed at an unloading station A on a carton positioning and supporting structure II located beneath the path of movement of a unit 6 as shown in Fig. 1. In that view, movement of the conveyor chains in a clockwise direction along their paths has brought the set of article engaging devices Iii, Ita of a unit 6 to a position directly over the cans (not shown) in the carton I6 at the unloading station A. That unit 6 includes a pair of depending rigid pusher bars I8, Figs. 1 and 3, which press against the trailing ends of the carton side flaps. See Figs. 4, 7 and 10 also. Further movement of the unloader conveyor will cause the carton I6 on the supporting structure ll, Figs. 1 and 7, to move forward in register with the overlying unit 6 which is also lowered so that its article engaging devices I4, Ida descend into the carton and engage the individual cans therein as indicated by Fig. 10 and as hereinafter will be more particularly described. The unit 5 then will be raised as the paths of the connected .portions of the conveyor chains turn upward. The cans engaged by the devices I4, Ifla of that unit will be lifted as a group from their carton and carried in suspension from the unit as shown for the unit 6 and supported cans I5 at about the middle of the lower portion of Fig. 1. The empty carton IB will in the meantime have been -pushed into a downwardly inclined extension I'Ia of the carton supporting structure. Further progress of the unit 6 and the cans carried thereby on the lower run of the conveyor Fig. l, will bring them to a position over a horizontal article take-away conveyor I9 as shown in the lower part of the left hand por-tion of Fig. 1. The article engaging devices I4, I 4a of the unit then will lbe actuated as hereinafter explained to deliver the cans i5 onto the oonveyor i9 for transport thereby as indicated for the cans I5 at the extreme left hand end of Fig. 1.

Details of the structure and operation thus generally described will now be given.

Referring again to Figs. 1, 2 and 1l, the framework structure I comprises vertically spaced longitudinal side members 22, vertically spaced end members 2l, and vertical corner members 22 assembled and rigidly connected together in any suitably known manner. The supporting uprights 2 are rigidly attached to the frame structure I adjacent to its corners.

The chain 5 of the unloader conveyor 3 is trained about a front sprocket 23, a rear sprocket 25 and an intermediate upper sprocket 25 and on its lower run passes over an intermediate lower sprocket 2t. The rear sprocket 24 is mounted on a short horizon-tal Xed shaft 21, Figs. 1 and 11, projecting inwardly from a holder 28, Fig. 2, on the far side of the frame structure I as viewed in Figs. 1 and 11.

The sprockets 23, 25 and 26 are mounted on short horizontal studs 29, 3@ and 3i respectively, parallel with one another and with shaft 21 and similarly mounted in holders on the far side of the frame structure, such holders being indicated at 32, 33 and 34, respectively, in Fig. 2.

The chain @l is at the near side of the apparatus as viewed in Figs. 1 and 11 and is trained about a front sprocket 35, a rear sprocket 36, and an upper intermediate sprocket 3l and on its lower run passes over a lower intermediate sprocket 38. These sprockets are rmounted on parallel xed short shafts 39, d, llI and 42, respectively, projecting from holders 43, 44, I5 `and 46, respectively, Fig. 2, mounted on the near side of the frame structure.

It will be observed that the front sprockets 23 and 35 are located at a lower level than the rear sprockets 2s and 3S. The upper intermediate sprockets 25 and 3l are located at a level such that the portions 5b and lib of the chains 5 and Il, respectively, stretching between these sprockets and the rear sprockets are horizontal while the portions 5c and Llc, respectively, or the chains stretching between them and the front sprockets 23 and 35 are downwardly inclined. Similarly, the lower intermediate sprockets 25 and 38, over which the chains pass are located at a level Such in respect to the front sprockets 23 and 35 and to the rear sprockets 213 and 32 that the chains move along upwardly inclined paths at 5d and lid, respectively, on rounding the front sprockets and travelling to the lower intermediate sprockets and then horizontally at 5e and 4e, respectively, from the latter to the rear sprockets. Each unit 6 carried by the chains will be lowered to the lowest point along its path when the chains are travelling in a clockwise direction as viewed in Fig. l and the portions of the chains to which the plate l of that unit is pivotally attached are at the bottoms of their paths around the front sprockets 23 and 35. AS previously stated, the article engaging devices of that unit will have been lowered into engagement with cans ina carton I6 moving on the carton support I1 directly beneath it oy the time the unit reaches the lowest level of its travel. Thereafter, the unit 6 and the articles engaged by its article-engaging devices will be raised as the unit supporting portions of the chains complete their travel around the front sprockets and move upwardly along their inclined paths toward the intermeddiate supporting sprockets 26 and 3.8K.

The axes of the article-engaging devices of the unit will be kept vertical during all movements oi the unit by its carrying chains.

The conveyor drive comprises a motor 4l on a cross supporting shelf 48 -mounted on the frame structure I, Figs. 1 and 2. Motor el has a driving connection at 49 with a speed reduction unit 50. The latter also is mounted on the same supporting shelf 43 and has a driven shaft 5I, Fig. 2, connected by a chain and sprocket transmission 52 with a countershaft 53. The iatter extends transversely across the frame structure I and may be journalled at its ends in suitable bearings 54, 2 carried by uprights 55 on the opposite sides of the frame structure. See Fig. 1 also. The countershaft 53 drives the rear sprocket 3S by a suitable chain and sprocket transmission indicated at'ii, Figs. 1 and 2. The rear sprocket 24 for the chain 5 is similarly driven from the countershait 53 by a chain and sprocket transmission 5l.

Fig. 1l illustrates the manner in which the carrier plate 'i of a unit 5 is maintained horizontal during its entire cycle of movements. Only the plate 'l of one such unit is shown in this view, the others being omitted for the sake of simplicity and clarity. This plate is shown in full lines in a position near the end of the lower run of its path of movement. The portion oi the chain 5 to which the attaching end strip 8 of the plate is pivotally attached is just starting to move from a stationary horizontal guide rail 53 upward around the rear sprocket 24.l At this time, the roller I2 at the same end of the plate? is starting to move from its course between vertically spaced horizontal portions 59a and 6ta of upper and lower stationary guide rails 59 and til, respectively, upward between arcuately curved portions 5% and Sb, respectively, of these same guide rails. At this time, the Vroller I3 at the near end of the plate I is moving in the air while the portion of the chain 4 to which the attaching end strip 9 is pivotally attached is beginning to move upwardly around a portion (not'shownof the rear sprocket 35.- The curvature of the guide rail portions 59band Eo corresponds to that of the chain-engaging peripheral portions of the sprockets 2c and 36 so that the plate I will be lmaintained horizontal while the portions of the chains attached thereto are passing upwardly around these sprockets.

On rounding the sprocket 24, the portion of the chain 5 to which the attaching bar 8 is con-4 nected will be horizontal and it may be supported and guided by a stationary horizontal guide rail 6I during part of itstravel to the upper inter'- mecliate sprocket 25.' Meanwhile, the roller I2 will pass underneath and along the under surface of a stationary guide rail 62. The roller I3 projecting from the near end of the plate will be moved through the air upwardly along an arcuate path at the inner side of the sprocket 35 vas the portion of the chain4 to which the attaching strip 3 is pivotally attached rounds that sprocket. Thereafter, the roller I3 will be moved horizontally in free air until it passes beneath and rides along the under surface of a stationary horizontal rail' 63. Meanwhile, ythe portion of Vthe chain 4 to which the'strip 9 is attached will move tremities.

along the upper surface of a stationary horizontal guide rail 64. Fragmentary portions of the strips 8V and 9, respectively, of a carrier plate (not shown) are shown by dot-and-dash lines near the middle ofthe upper part of Fig. ll. At this time, the rollers I2 and I3' carried by the same plate will be riding under the stationary railsv 62 and 53, respectively at the positions shown by dot-and-dash lines. After passing over the sprockets 25 and 3l, respectively,y the portions of the chains 5 and 4 to whichthese strips t and 9 are attached will be moved along downwardly inclined paths to the front sprockets 23 and 35, respectively. On rounding the sprockets 23' and 35,' vthese portions of the chains 5 and 4 to which the strips 8 and 9, respectively, are attached will move between vertically spaced lstationary inclined guide rails 54, 55 and, 57, respectively. When the strip 9 is rounding the sprocket 35, the roller it carried by the same plate will rbe moving along a guide slot between arcuately curved upper and lower stationary guide rails 68 and 69, respectively. This condition is indicated by a dot-and-dash line showing of a strip and a roller I3 in the lower part of ll. At this time, the roller I2 and the strip at the far end of the same plate will be at the positions also indicated by dot-and-dash lines in the middle.V of Fig'. ll. Thereafter, the roller I2 will be guided between vertically spaced inclined stationary guide rails i8 and '1i onto the upper surface of the horizontal portion 60ct of guide rail 5c ywhile the portion of the chain to which the strip S is attached passes up the inclined way between the guide rails 64 and 55, over sprocket 2E and then between vertically spaced horizontal stationary guide rails I2 and 53. The portion of the chain 4 to which the strip 5 tached will move meanwhile between the inclined stationary guide rails @e and 6l, over the sprocket 38 and then between vertically spaced stationary horizontal guide rails ifi and "i5, respectivelyll The roller I3 of the same plate will be moved at this time through the air until it encounters the upper' surface of an inclined stationary guide rail '1 6 by which it will be guided for a distance on the way to the position shown in full lines in Fig. 11.

Referring now to Figs. 3, 5 and 6, it will be noted that each article engaging device is of a unit comprises a vertically disposed tubular body member 'I'I -securely fastened against the under side of its plate `I, as by cap screws "it, Fig. 6, in axial alignment with a vertical opening i8 in the plate l, Fig. 5, this for a purpose presently to be described. The body I'I is provided with a plurality of vertical slots 8E? through its wali, there being two diametrically opposite such slots in the example shown as appears from Fig. 5. Cooperative hanging rigid tong or gripper arms 8| have their upper portions disposed in these slots and pivotally attached to the body member 7.1 by horizontal pivot pins 32 spanning the slots. These tong or gripper arms have inwardly projecting hooks or bills Sie at their lower free ex They also have inwardly extending im tegral arms SIb extending from their pivoted upper portions into and toward the vertical center line of an axial space or chamber 83 in the body member TI. The inner ends of these actuating arms bear against the lower end of a plunger 84 which extends downwardly through the opening i9 in the plate 'I into the chamber 8 3. A compressed coil spring 85 in the chamber 8i;4 rests upon the hoor of kthat chamber and is of the same plate is at- Y surmounted by a disc 88 which it presses against the under sides of the actuating arms lb of the tong members so as to tend to raise these arms as far as possible. This, of course, tends to swing the lower hooked ends of the hanging tong or gripper arms 8| toward each other.

An axially bored centering taper plug or inverted cone 81 is slidable on a tubular member 88 which depends from the body 11 in axial alignment therewith. Member 88 may be integral with the body 11 or a separate element which is held rmly pressed against the bottom of the member 11 by a supporting bolt 89 and a washer S8 interposed between the bolt head and lower end of tubular member 88, the shank of the bolt extending through the bolt hole 9| in the bottom of the body member 11 and being engaged by a nut 92 located in the body member chamber 83. The washer 98 is sufficiently larger in diameter than the lower end of tubular member 88 to underlie the bottom of the centering taper plug 81 sufficiently to support the latterl on the member 88 when it is at the lower limit of its Vertical sliding movement on such member. A vertical guide pin'93 projects upwardly from the taper plug 81 into a vertical guide slot or opening Sli, Fig. 3, in the lower end portion of the body member 11 so as to prevent independent turning of the centering taper plug about its vertical axis. The plug 81 may limit the inward or closing swinging movements of the hanging tong or gripper arms 3|. Such plug may be a hollow shell made oi chromium plated metal or other suitable material and provided with an integrally formed central hub or internal sleeve portion 95 fitting slidably on the supporting tubular member 88.

Each article engaging device as just described is identical with every other one of a unit 6 except that the outer tong arms 8| may be omitted from the devices at two diagonally opposite corners of a rectangular group comprising four of these article engaging devices per row in one direction and six such devices per row in a direction at a right angle therewith, as shown in Fig. 4. This arrangement provides article-engaging devices of the same number and the same relative positioning as the cans I5, Fig. 7, in a carton i8 to be unloaded. rEhe two diagonally opposite corner devices I4 from which the outer tong arms are omitted are marked Mia and appear to advantage, in Fig. 4. Corner devices |80. also appear in Figs. 3 and 10. It will be clear from Fig. 4 that the omission of tong arms from these two corner devices is to enable lowering of the entire set of article engaging devices of a unit sufficiently into an underneath carton to engage the upper ends of all the twenty-four cans therein and that, without such omission, the corner tongs would strike the top or catch on the outer wall of the carton. The corner cans engaged by these single tong-arm corner devices will be lifted with the other cans since their contact with the adjacent cans as the entire assembly is raised will keep them engaged with the single tong arms until such arms are opened in unison with the other tong arms, as presently will be described. It will be understood that the carrier plate 1 of each unit is of approximate width and length to permit attachment of the requisite number of article-engaging devices to the under side thereof with the individual devices suitably spaced and relatively arranged according to the spacing and relative arrangement of the cans in the carton to be unloaded and individually preset angularly about their respective vertical axes to obviate interference between adjacent tong arms. See Fig. 4.

The tong members 8| of the article-engaging devices are spring pressed continuously toward closed position by means hereinbefore described. As the carrier plate 1 with these devices dependent therefrom is moved downward into the waiting carton at the unloading station, the centering plugs 81 enter the open upper ends of the cans and may ride upward on their supporting members 88 by reason of their contact with the rims of the cans while the unit 8 as a whole is still moving downward. The free, hooked lower ends of the tong arms will slide downward over the rim beads a of the cans and snap closed beneath such beads. The engaged positions of some of these article-engaging devices with cans in the carton are shown by Fig. 10. The cans are close together in the carton as indicated and to prevent interference between adjacent centering plugs, the upper portions of these plugs may be partially cut away or formed with flat portions 81a. The outer surface of the plug is in Contact between the cutaway or flat side portions 81a with the internal surface of the can at its rim and centers the can properly for the tongs. This Contact is very light, being substantially a line contact when the can is truly cylindrical and of standard dimensions. The light contact is advantageous in preventing marring of the internal surface of the can, particularly if such surface is lacquered or otherwise coated and also aids release of the cans when the tongs carrying them are opened. Cans internally bent or distorted somewhat but not to suflicient extent to make them unsuitable for use will be engaged by the article-engaging devices. While the opening and closing movements of the tongs are but slight, the cans fit tightly in the carton and this tends to cause interference between adjacent tong members of adjacent devices. Such interference is obviated by attaching the respective article-engaging devices to their carrying plate in angularly turned positions such that adjacent tong members of adjacent article-engaging devices lie in difierent vertical planes so that they may open without striking each other. See the showing in dotted lines of open positions of two adjacent tong members 8| in the lower left hand corner portion of Fig. 4. This also aids all outside tongs to clear the walls of the carton.

The plungers B4 are rigid elements carried by a horizontal opening plate 96 which overlies the carrier plate 1 and has outwardly projecting apertured corner ear portions 81 fitting slidably over upstanding fixed studs 88 on the plate 1.`

See Figs. 2 and 3. Coil springs 99 beneath the ears 91 press washers |88 upwardly against such ears so as to tend to maintain the opening plate 98 raised as far as possible, this being limited by stop nuts IUI on the upper end portion of the studs 98. Screw threaded stop elements i82 depend from the opening plate 96 toward the plate 1 with which they will contact on a predetermined downward movement of the plate 96 to limit the downward working movement of the plate 86. A lever for forcing the plate downward comprises a pair of spaced lever bars |83, Fig. 2, connected at one end by a shaft |84 which is pivoted in fixed bearing blocks |85 on the plate 1. The lever bars |83 are connected intermediately by a cross shaft |86 which extends through apertured upstanding lugs |81 on the the sprocket 26.

, 9 opening lplate 96. The lever bars W3 are connected at their free ends by a cross bar Ille which carries spaced rollers 09. During movement of a unit E with the articles carried thereby along allower run of the unloader conveyor, the rollers |09 encounter the under surfaces of yieldable cam levers IIG. These are shown in dotted lines in Fig. 2 and one of them is shown in Fig; l. The lower cam surface of each of these levers is formed as indicated at IIi in Fig. 1 to 'bias the free end of the opening lever downward so as to depress the opening plate 9S and force the plungers 84 downward in the individual article engaging devices. In consequence, the tongs of such devices will be opened to release the articles carried thereby. rthis action takes place when the unit 6 is over the article take-away conveyor I9 as hereinbefore has been stated. The cam levers IIS) arel intermediately pivoted on a stationary cross sli-aft I Ita. and tension coil spring means H2 yieldingly urge their forward camming end portions downward to a limit set by'contact of their rear portions with stop means IIOb, Fig. 1.

. The carton supporting and positioning structure Il comprises a pair of spaced normally horizontal side frame members I I3 extending below the front end portion of the frame structure I and supported at its front end on a transverse horizontal pivot shaft I I4, Fig. l. The side frame members are connected at intervals by transversely disposed rollers H5, the peripheries of which extend slightly above the level of the upper edges of the side members IIS. Coil springs, indicated at II! in Fig. l, connect the side members IIS with the main frame structure so as yieldinglyfto retain the pivoted cartonsupporting structure I'i-I'la in its normal horizontal position, against xed stops, one of which is shown at 2 Il' in Fig. 7.

The carton I6 containing the articles to be unloaded may be placed in a predetermined position on .the rollers H5 by suitable carton feeding means (not shown) or manually. As thus spotted on the structure Il', the front wall of the carton bears against a raised downwardly retractile stop element H3. This is the upturned free end of an angularly shaped arm II9 of lever IZB which is fulcrurned on a transversely disposed shaft I2I extending between the frame members f I I3. The lever E2@ is operable by an upwardly projecting actuating arm m2 connected by a connecting rod I 23 with the lower end of a vertically disposed. lever I2@ which is intermediately fulcrumed on a horizontal shaft 25 carried by a side wall member of the main frame work I. The upper end of lever i213 carries a cam roller m6 bearing against the periphery of a cam I2? on Sprocketgii makes one revolution per unit S. Cam I2? is rotated with that sprocket and hence` driven in synchronism with the unloader conveyor carrying the article removal yunits A suitable spring (not shown) may be provided to maintain the cam roller 26 in` bearing contact with the periphery of cam |21 if the weight oi the connected parts is not suficient to accomplish this result without the use Aof such a spring. The cam contour is such that the carton stop I I3 will beretracted downwardly at a suitable time in a cycle of operations ofthe, unloader to permit forward lmovement of thecarton along theroll-way of structure il underpressure applied thereto by the depending pushersls of the particular unit 6 that is then in position to unload such carton. As previously explained, the forward movement of the carton by pushers I8 will be in register with the assembly of article-engaging devices of the overhead unit 6 as these devices are lowered to their articleengaging positions, thisdespite the variation of the horizontal speed of the conveyor carrying the units 6. After the. articles have been gripped and by the time they have been extracted from the cartomthe pushers I8, which depend a considerable distance below the associate articleengaging devices, vwill have pushed the empty carton from the horizontal series of transverse rollers H5 ontoand jdown an inclined series of transverse rollers l|28Y which are mounted in a downwardly inclined extension Ila of the carton supporting structure; In. lieu of the pushers I8 carried by each unit'l, the contact of the centering plugs 37 ofthe. unit with the cans in the carton being unloaded could be utilized to effect the desired Vforward movement of the carton. TheA use of pushers is preferred.

When the cans are set down on the article removal conveyor I9', ythe plugs of the articleengaging devices involved in their transfer will steady them against the possibility of tipping over and onto theconveyor i9. The conveyor I9 is, of course, driven in synchronism with the unloading conveyor and the, plugs will be raised away from the cans shortly after they have been deposited.

The spotted position ofr a carton at the unloading station may vary slightly either transversely of the carton positioning structure Il or longitudinally thereof and the taper of the centering plugs of theA article-engaging devices will assure accurate centering of usable cans in relation to the attaching devices so4 that such cans will be rmly gripped andextracted from the carton. If a carton shouldtcontain an excessively deformed or squashed `can or a can closed at its top, the pressureA thereonfrom the descending unit 6 will depress the forward end of pivoted structure I I so' that the carton and its contents will be discharged from the structure i? without being unloaded.

The invention provides means to hold down a carton during unloading as well as such of its aps as requirepholding down. As shown, Figs. 2 and 7, a xedhorizontal hold down guide IZl is provided at the unloading station A over a side portion of the rollway structure Il to hold down the end flap I 30 ofthe carton at that side of the rollway. As shown in Fig. 7, the carton is spotted with its side flapsvili and I32 respectively disposed in leading and trailing positions in relation to the body of the carton and with a second end flap L33 at the opposite side of the rollway froml stationary hold-down guide Iii. A movable hold dowfn lmeans for the leading side flap I 3Iv and the end flapk I33 comprises a pair of cooperative horizontally disposed hold down bars |34 and yI'ai, respectively, the bar I3@ being pivotedon a vertical pivot element IM located at the carton infeed end ofthe rollway near one corner. thereof while the bar |35 is pivoted on a vertical pivotelement |37 located at `the saine sideof the rollway but ina more forward location. These arms yISII and i3d have outwardly turned actuating arms I3la and 135e, respectively, connected by a coil'spring |33, tending to swing them laterally about their respective pivotal axes toward the longitudinal medianfline of the rollway. A stop 39 projecting `Afrom the arm ISM against a-xed abutmentfas one of the uprights as shown in Fig. 7, limits inward swinging movement of arm |3d. A projecting stop element |40 on the inner end of arm bears against a fixed stop element MI carried by the free end of arm |34 to limit the inward swinging movement of arm |35. A headed stud |432 on the free end of arm |35 works in a slot |43 in a stationary horizontal bracket arm |415 to guide and stabilize the swinging movements of arm |35.

With the arms |34 and |35 in the positions shown in Fig. 7, both the carton end iiap |33 and the leading carton side iiap |3| are retained in their open, outwardly bent positions. The opposite carton end iiap, |35, at the opposite side edge of the rollway is underneath the stationary hold down bar |29. The inner side edge portions of the arms |311 and |35 may at this time extend inwardly beyond the plane of the adjacent end wall of the carton proper. As the carton is moved forward on the rollway by the pushers i3 of the overlying moving units E, the arm i341 will be swung laterally outward by the contact of its obliquely extending inner side edge E with one of moving pushers i8. This will cause outward swinging movement of the arm |35 also, the element lili carried by the arm ISE transmitting motion to the projection |40 on the adjacent end of the arm |35. The laterally swingable hold down arms thus will be moved out of the Way of the descending article-engaging devices of a unit 6. As shown in Fig. 8, the carton has been advanced on the rollway to a position such that the can engaging devices of a unit 6, which are not shown in that View, will have been lowered into engagement with the cans in the carton. pusher i8 which has been biasing the arm |34 outward passes beyond the free end of that arm and releases it so that it swings inward to position to hold down the leading side flap and the right hand end flap of the next carton in line, as shown in Fig. 9. Meanwhile, the arm |35 is actuated by the pusher I8 and is biased laterally outward so as not to interfere with the upwardly moving cans as they are lifted from the carton. When the pusher |8 passes a little further beyond the position shown in Fig. 9, the arm |35 will be released therefrom and will be returned inwardly by the action of the spring |38 until the projection |40 strikes the stop element IM, the two arms, |34 and |35, respectively then being again in the positions shown in Fig. 7.

When the cans which have been extracted from a carton and carried by the article-engaging devices of a unit 6 to a delivery position over the take-away conveyor I9 are set down on that conveyor, the plugs of the article-engaging devices will steady the deposited cans against the possibility of tipping over and stabilize their positions on the conveyor |9 until such plugs are lifted out of the deposited cans by an upward divergence of the unloader conveyor from the plane of the take-away conveyor. The latter may of course be driven by suitable means, not shown, at the same linear speed as the unloader conveyor.

It will be obvious that apparatus of the invenm tion may be used to engage, transfer and deposit multiple containers and like articles under widely differing conditions and for specically different purposes. For example, the apparatus may be readily adapted and used to deposit the transferred group of articles ina case or carton or other receptacle rather than on a at horizontal conveyor and such articles might be picked up from a moving conveyor or similar support in- On further movement of the carton, the

stead of from a carton or case. Also, many changes in and modications of the illustrative apparatus shown in the accompanying drawings and herein particularly described will be obvious to those skilled in the art and we, therefore, do not wish to be limited to the details of such illustrative embodiment of the invention.

I claim:

1. In combination, a continuously moving endless transfer conveyor having a path of movement such that each of successive transverse portions of the conveyor descends to and ascends from a low level position during a cycle of movements thereof, a support extending beneath said low level position and on which a carton open at its top and containing a plurality of upright containers may be placed and be moved rectilinearly along a horizontal path passing directly beneath and beyond said low level position, a plurality of article engaging devices corresponding in number and relative arrangement with the containers in said carton and suspended from a transverse portion of the conveyor so that the axes of the individual devices are vertical at all positions, the containers in said carton being disposed in a plurality of cross rows therein and the article engaging devices likewise being arranged in a plurality of cross rows suspended from the transfer conveyor, said devices being constructed and arranged automatically to supportingly engage upper end portions of the containers in said carton when the portion of the conveyor carrying said devices has descended to said low level position and the carton has been moved on its support to a position directly therebeneath, said devices thereafter acting to lift the containers engaged thereby from the carton as the portion of the conveyor carrying said devices ascends from said low level position to a higher level portion of its path of movement, and carton pushing means carried by said conveyor in position to engage the carton on its support preceding completion of downward movement of the article engaging devices into engagement with the containers in the carton and thereafter to move the carton in register with the article engaging devices during their descent into supporting engagement with the containers in the carton.

2. The combination dened by claim l wherein said carton pushing means is moved by said transier conveyor to propel the carton on its support beyond a position beyond said low level position of the conveyor as the containers are lifted from the carton by the article engaging devices.

3. The combination dened by claim 2 wherein said support for the carton comprises a horizontal portion o n which the carton may be moved during lifting of the containers therefrom and a further downwardly inclined portion constituting a slideway for the empty carton.

4. The combination defined by claim 1 wherein the support on which said carton may be placed and moved comprises a normally horizontal structure pivotally supported at its carton infeed end at a predetermined level by a transverse supporting pivot element and yieldingly supported adjacent to its opposite end by spring suspension means, said spring suspension means permitting the support to pivot downwardly under pressure from the article-engaging devices to discharge the carton and its contents from the support should an obstruction in the carton in the path of downward movement of the article-engaging devices prevent full descent of such devices to 13 their operative article-engaging position in the carton.

5. The combination donned by claim l wherein said support for the carton comprises a normally horizontal structure and, in addition, a normally raised downwardly retractile stop projecting above the carton supporting surface of said structure to spot the carton on the support at a position in advance of the low level position of the transfer conveyor, means operable in synchronism with descent of the article-engaging devices to retract said stop downwardly to permit forward movement of the carton when said devices have been brought to a position above and in register with the containers in the carton, and pusher means` operating then to move said carton forward on its support in register with said article-engaging devices.

6. In a multi-article transfer apparatus, a horizontal carrier plate, a plurality of cross rows of article engaging devices depending from the under surface of said horizontal plate, each device comprising a vertical body fixed to the plate, an article centering taper plug carried at the lower end of the body for limited free vertical movements relative to the body, a single pivoted tong member at the inner side of the body of each of the two devices located at diagonally opposite corners of the assembly carried by the plate, a pair of cooperative pivoted tong members carried by the body of each of the other article-engaging devices of the assembly, spring means urging said pivoted tong members to their closed positions, normally raised plungers mounted for limited vertical movement and operative when lowered to actuate said tong members to swing them to their open positions, and means common to all said plungers for actuating them in unison.

7. The combination defined by claim S wherein the means to actuate said plungers in unison comprises a vertically movable horizontal opening plate supported above said carrier plate and carrying said plungers, spring means tending to maintain said opening plate raised in relation to the carrier plate, and means for depressing said opening plate to lower said plungers.

8. The combination dened by claim 6 wherein the bodies of the respective article engaging devices are xed to said carrier plate in preset angularly turned positions so that adjacent pivoted tong members of adjacent article engaging devices open and close in different vertical planes without contact with each other.

9. In a multi-article transfer apparatus, a transfer conveyor comprising a pair of transversely spaced and staggered endless conveyor chains mounted to move along endless paths lying in parallel vertical planes and a transversely disposed, horizontal carrier plate extending between corresponding portions of said chains and attached pivotally thereto solely at two diagonally opposite corner portions thereof so that said plate will remain horizontal during all travel with the conveyor chains, means to drive said chains continuously, a plurality of article engaging devices xed to and depending from the under surface of said carrier plate in a plurality of cross rows corresponding in number and relative arrangement of components with cross rows of containers in a carton to be unloaded, means to support such a carton with the containers therein at an unloading station beneath a portion of the path of said plate and so that said carton may be moved horizontally with the plate during the unloading operation, said carton having outwardly turned flaps at the sides and rearwardly and forwardly turned flaps at the rear and front, respectively of its open upper end, stationary hold-down means for the outturned ilap at one side of the carton upper end, and laterally swingable, pivoted hold-down means for the iiap at the opposite side and the forwardly turned flap at the front of the carton upper end.

10. In a multi-article transfer apparatus, a transfer conveyor comprising a pair of transversely spaced and staggered endless conveyor chains mounted to move along endless paths lying in parallel vertical planes and a transversely disposed, horizontal carrier plate extending between corresponding portions of said chains and attached pivotally thereto solely at two diagonally opposite corner portions thereof so that said plate will remain horizontal during all travel with the conveyor chains, means to drive said chains continuously, a plurality of article engaging devices fixed to and depending from the under surface of said carrier plate in a plurality of cross rows corresponding in number and relative arrangement of components with cross rows of containers in a carton to be unloaded, means to support such a carton with the containers therein at an unloading station beneath a portion of the path of said plate and so that said carton may be moved horizontally with the plate during the unloading operation, said carton having outwardly turned flaps at the sides and rearwardly and forwardly turned flaps at the rear and front, respectively, of its open upper end, stationary hold-down means for the outturned flap at one side of the carton upper end, laterally swingable, pivoted holddown means for the flap at the opposite side and the forwardly turned flap at the front of the carton upper end, and rigid pusher means depending from said carrier plate to engage the carton at its rear when the plate has arrived at a predetermined point along its path and thereafter to move the carton forward on its support in register with said plate during movement of the plate along a further part of its path, said rigid pusher means being operable to swing said movable flap hold-down means laterally outward during this registering movement of the plate and the carton to clear the space above the upper ends of the containers in the carton to permit engagement of said container upper ends by the article-engaging devices carried by the plate.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 662,709 Clay Nov. 27, 1900 1,050,521 Cunning Jan. 14, 1913 1,742,074 Hires Dec. 31, 1929 2,000,417 Perry et al. May 7, 1935 2,119,725 Stecher June 7, 1938 2,213,774 Taylor Sept. 3, 1940 2,253,283 Minaker Aug. 19, 1941 2,335,613 Sayen Nov. 30, 1943 2,578,912 Waters Dec. 18, 1951 

